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F♯ Half Diminished

Notes: F♯ - A - C - E | Degrees: 1 - ♭3 - ♭5 - ♭7 | Written: F♯m7♭5, F♯ø7, F♯ø

Construction: Root, Minor 3rd, Diminished 5th, Minor 7th

It is a diminished triad with an added minor 7th, giving it a dark, moody, and tense character commonly used in jazz and minor key progressions

Fingering: RH 2-3-4-5, LH 5-4-3-2

Inversions: Root F♯m7♭5 - 1st F♯m7♭5/A - 2nd F♯m7♭5/C - 3rd F♯m7♭5/E

G♭ Half Diminished
This is the same chord as G♭ Half Diminished: the same keys on the keyboard, spelled with flats.
Related boards
F♯m7♭510 st, 138.0 mmRoot position, figured bass 7

F♯3, A3, C4, E4

Fingerings

Root position: either hand, fingers low note to high
HandNotesFingers
RightF♯, A, C, E2-3-4-5
LeftF♯, A, C, E5-4-3-2

Close-position standard fingering: either hand takes the whole shape. Thumb is 1, little finger is 5.

F♯ Half Diminished 7th: notes and degrees

F♯m7♭5 contains F♯, A, C and E. A diminished triad with the minor seventh added on top.

Scale degree, note, and interval measured from the root.
DegreeNoteInterval from rootSemitones
1F♯Perfect unison0
♭3AMinor third3
♭5CTritone6
♭7EMinor seventh10

F♯ is a black key; A, C and E are white.

Construction

F♯ Half Diminished = Root + Minor 3rd + Diminished 5th + Minor 7th = F♯, A, C, E
NoteIntervalDegree
F♯Root1
AMinor 3rd♭3
CDiminished 5th♭5
EMinor 7th♭7

Fingering

NoteKey colorRight handLeft hand
F♯blackindex finger (2)little finger (5)
Awhitemiddle finger (3)ring finger (4)
Cwhitering finger (4)middle finger (3)
Ewhitelittle finger (5)index finger (2)

Right hand: index finger (2) on F♯, middle finger (3) on A, ring finger (4) on C, little finger (5) on E.

Left hand: little finger (5) on F♯, ring finger (4) on A, middle finger (3) on C, index finger (2) on E.

F♯ Half Diminished Inversions

  • Root position
    F♯ – A – C – E
  • 1st inversion (F♯m7♭5/A)
    A – C – E – F♯
  • 2nd inversion (F♯m7♭5/C)
    C – E – F♯ – A
  • 3rd inversion (F♯m7♭5/E)
    E – F♯ – A – C

Key Signature

A Half Diminished chord is built from symmetrical or ambiguous intervals, so it doesn't belong to a single key and has no key signature of its own.

Chords in the Key of F♯ Major

These are the triads built on each degree of F♯ Major:

C1C2C3C4C5C6C7C8F♯A♯C♯
IF♯ Major (major)
DegreeNumeralChordQuality
1IF♯ MajorMajor
2iiG♯ MinorMinor
3iiiA♯ MinorMinor
4IVB MajorMajor
5VC♯ MajorMajor
6viD♯ MinorMinor
7vii°E♯ DiminishedDiminished

How F♯ Half Diminished functions in a key

The same chord takes on a different harmonic role depending on the key it appears in. Here is where F♯ Half Diminished sits diatonically across the common keys:

  • In G major, F♯ Half Diminished is the vii° chordthe dominant.
  • In E minor, F♯ Half Diminished is the ii° chorda predominant.

Scales That Include the F♯ Half Diminished

Same Notes, Other Names

The notes F♯ – A – C – E aren’t exclusive to this chord. Depending on which note is the bass and how the chord functions, the same pitches also spell:

F♯ Half Diminished : Frequently Asked Questions

What is the F♯ Half Diminished chord on piano?
The F♯ Half Diminished chord contains the notes F♯ – A – C – E. On piano, play these notes together to sound the chord.
What is the F# piano chord?
The F# piano chord (written F♯ Half Diminished) uses the same keys: F♯ – A – C – E. The # and ♯ symbols name the same black key.
What notes are in the F# Half Diminished chord?
F# Half Diminished is built from the F# root. Check the interactive keyboard above for exact notes and fingering.
How is the F# Half Diminished chord used in music?
F# Half Diminished appears in jazz, pop, and classical contexts. Its sound depends on the chord quality (Half Diminished).
What is the fingering for F# Half Diminished?
See the fingering chart above. Right hand typically uses thumb on root. Left hand uses pinky on root.
What are the inversions of F# Half Diminished?
Use the inversion buttons above to see each inversion with notes, fingering, and staff notation.
What is the ii-V-i progression with F# Half Diminished?
F# Half Diminished functions as the ii chord in minor-key jazz harmony, resolving through the V7 to the minor tonic.

F♯ Half Diminished 7th in detail

Exact

Every pitch class is present and nothing outside the chord is added.

TypeNotesSemitonesSpanOmissions and additionsSet relationFit
Close, root positionF♯3 A3 C4 E410138 mmnoneidentical
Close, first inversionA3 C4 E4 F♯49124 mmnoneidentical
Close, second inversionC4 E4 F♯4 A49124 mmnoneidentical
Close, third inversionE4 F♯4 A4 C58110 mmnoneidentical
Drop 2C3 F♯3 A3 E416220 mmnoneidentical
Drop 3A2 F♯3 C4 E419261 mmnoneidentical
Drop 2 and 4F♯2 C3 A3 E422303 mmnoneidentical

Reduced

A subset of the pitch classes: the identity is incomplete rather than altered.

TypeNotesSemitonesSpanOmissions and additionsSet relationFit
Shell, root ♭7 ♭3F♯2 E3 A315206 mmomits Csubset
Guide tones, ♭3 and ♭7A3 E4796 mmomits F♯ and Csubset
Rootless closeA3 C4 E4796 mmomits F♯subset

Spans are measured centre to centre at a 165 mm octave (standard keyboard geometry).

Which keys it belongs to

KeyRoman numeralFunction
E minoriim7♭5Predominant
G majorviim7♭5Dominant function

Classification system: common-practice functional harmony.

Change one note

Chords a single note away, and what moving that note does.

ChordChangeFormulaCommon tones
F♯dimdrops E1 ♭3 ♭53
F♯m7C becomes C♯1 ♭3 5 ♭73
F♯dim7E becomes E♭1 ♭3 ♭5 ♭♭73
F♯m9C becomes C♯, G♯1 ♭3 5 ♭7 93
F♯mC, E becomes C♯1 ♭3 52
F♯7A, C becomes A♯, C♯1 3 5 ♭72
F♯mMaj7C, E becomes C♯, E♯1 ♭3 5 72
F♯aug7A, C becomes A♯, C×1 3 ♯5 ♭72
F♯7sus4A, C becomes B, C♯1 4 5 ♭72
F♯m6C, E becomes C♯, D♯1 ♭3 5 62

Frequencies

NoteMIDIFrequency
F♯354185.00 Hz
A357220.00 Hz
C460261.63 Hz
E464329.63 Hz

Reference pitch A440, 12-TET, close root position.

Set theory: prime form, Forte number, interval vector
Absolute pitch class set
{6, 9, 0, 4}
Normal order
[4, 6, 9, 0]
Prime form
(0258)
Forte number
4-27
Interval vector
<012111>
PairIntervalSemitonesInterval class
F♯ to AMinor third33
F♯ to CTritone66
F♯ to EMinor seventh102
A to CMinor third33
A to EPerfect fifth75
C to EMajor third44

Where these facts come from

Every value on this page is derived from the note formula for a half diminished 7th applied to the root F♯, using standard music theory. Nothing here is hand-entered per chord, so the notes, intervals, inversions and frequencies cannot drift out of agreement with each other. Pitches assume 12-TET at A440.